Engine Shutdown When In Regeneration Mode

[Coalsmoke]

Tom, I can hear it as well, sounds almost like the exhaust brake is on while in regen at idle. That and the hot exhaust sound once shut down gives it away. That said, I like my insight, it tells me what's going on more or less.

 

[HBarlow]

Tom,



I can hear the rumble sound and I'm older than you and my hearing is probably worse, as well. But the exhaust note change is, at least for me, a less reliable indicator of regen mode than the pyrometer. In other words, I occasionally hear the rumble and verify regen mode by consulting the pyrometer but more often I discover the engine is in regen by looking at the pyrometer and don't hear the changed exhaust sound.

 

[tom sweeney]

howdy fellas!!!..... there's no question a pyrometer would show the regen process `much easier... i simply mentioned the "sound" because i don't have a pyro installed yet!!!... . nice to hear from you Harv... . hope all is well on your end!!!... ... ... ... ... tom

 

[HBarlow]

Somebody asked that question at May Madness, the Rep from Rocky Mountain Cummins was there to answer questions. He said go ahead and shut it down, it doesn't hurt anything. The turbo is watercooled so you don't have the same temp issues as the earlier gens did. Also, the regen mode is automatic and will resume when you drive it again. As far as an indictor light, he said Dodge didn't want one because our trucks are consumer products and it would likely confuse most people. The regen system is designed to run in the background.

Allnew2Me,



It was me, sitting on the front row, who made a nuisance of myself asking all the questions about hot shut down and regen mode on the new 6. 7 engines of Scott Bentz of Cummins Rocky Mountain as well as other speakers.



I did not understand the reply quite like you did. My impression was that the speaker, although very knowledgeable about Cummins products and trying to be as helpful as he could, admitted that he was not very familar with the 6. 7 Cummins engines installed in the 2007-2008 Ram trucks. The Cummins 6. 7 he is familiar with, the one installed in MDTs, does not have the same emission control equipment our Dodges have.



He seemed to have the opinion that hot shut downs probably wouldn't hurt the engine but I wanted a more definitive answer from the folks at Cummins who actually build the engine intended for our Dodge platforms. Unfortunattly I wasn't able to get the kind of authoritative info I was seeking.



I have tried obtaining technical info from Dodge. It simply can't be done. Apparently Dodge employs a few new college graduates or maybe just high school grads who can read well and equips them with a factory brochure and parks them in front of a telephone. I tried very hard to get the rear spring ratings of the 3500 pickups and chassis cabs several months ago before I ordered my cab and chassis. The airhead I spoke with didn't even understand what I wanted. She knew half as much as I do and understood considerably less.



Each to his own but I do not plan ever to shut mine down unless egt is below 350*. A watercooled turbo probably helps some but the flow of water stops when the engine is shut off, just as oil flow through the bearings does. The owner's manual cautions never to shut down hot. It provides a table depending on operating mode just before stopping and recommends a delay of "less than one minute" to "five minutes" of idle time before shut down. The instructions in the owner's manual overlook "regeneration mode shut downs. " If it is in regen mode I will either drive it or turn off the cruise control/fast idle mode and allow the ECM to ramp up to 900 rpm and continue regen, get out and lock the doors and let it run... ... unless I'm in a public place in CA, CO, OR, MA, or NY where treehuggers rule and the green cops will ticket me for idling.

 

[donnandon]

Harvey, just wondering if a turbo timer would satisfy the regen/shutdown question? You could set it for the most they recommend (5 minutes) and truly walk away and the truck will turn itself off. I have been considering this for when we tow our trailer and don't want to sit in the truck for 5 minutes before shutting down.

 

[HBarlow]

DBracey,



It probably would. That might prove to be a good idea.



I have only observed the situation I described above once where, when after observing the truck was apparently in the regen mode I disabled the cruise control/fast idle feature and allowed the truck to idle a couple of minutes. The ECM ramped up idle speed and EGT climbed back up to 600* - 800* apparently resuming regen. I walked away from the truck and left it "cooking" for a few minutes. When I returned, idle speed had dropped to normal and EGT had cooled to shut-down range so I shut it down. I didn't think to time the process but it was probably 5 to 10 minutes.



I'm still learning about this truck and engine so probably haven't seen all it's tricks. I certainly haven'tr figured it all out yet.

 

[sag2]

The newest flashes enable "net zero" operation where the idle speed will increase by itself and the truck will actually burn more soot than it is generating. But I still believe you guys are over thinking this. There is nothing wrong with shutting down during regeneration. If it does not complete on that run cycle, it will start on the next run cycle. As for the extra heat being produced, as was said earlier, it is mostly in the exhaust system. CAT's and exhaust run at very high temps on any vehicle, and they get shut down hot all the time with no negative effects. The turbo is water cooled and also very robust when it comes to heat. Although I don't have a 6. 7, all three of my 5. 9's were shut down hot with no negative effects. I only let them idle if I came off the freeway to a rest area, and only for a short time. Most of the time the truck ran very slow while parking or going through my neighborhood. Also if you watch the majority of Cummins owners, they drive them just like gas trucks, again with no negative effects.

In the diesel class there are also no special precautions about shutting down during regen, and none of the TSB's have made any mention of it either.

 

[HBarlow]

sag2,



Thanks for the information. I'll give your comments some thought.

 

[mcurtice1]

I am a little confused reading through this thread. I have gauges on my truck and get the following readings:



Start Up: 400 - 600º

Operating Conditions: 800 - 1000º

Regen: 1300 - 1400º

Cooling Down: 500 - 650º



I don't shut my truck off unless it is below 600º. Other postings are saying they are in regen in the 600 - 800º? This is very low from my experience.



I have never seen a time that the regen was running when I went to shut off the truck. If I am in regen and hit the brake, generally the regen will stop and then restart when I am back on the throttle.

 

[Bob4x4]

My personal experience has been that it must be in Drive to regen... ... ... ... .....



Bob

 

[HBarlow]

mcurtice1:



My truck is a 2008 cab and chassis so some differences are expected. Cab and chassis trucks meet 2007 environmental wacko standards, not 2010 as the 6. 7L pickups must do.



I don't know how the engine programming differs but know that it differs in at least some ways, probably safe to assume it differs in a number of ways.



My temps would be more in this range:



Start Up: 200* - 300*

Operating: 600* - 800* (same)

Regen: 600* - 1000* (at idle)

Regen: 800* - 1000*

Cooling: 200* to 300*



My gauges are DiPricol Optix, obtained from Geno's, installed by a friend who is a former Dodge dealership tech. The same gauges were installed in my previous '06 Ram, used for 238k miles, and later removed and reinstalled in the '08. The pyro probe is installed in the center of the exhaust manifold and the gauges operate correctly and readouts are in a normal range.

 

[HBarlow]

My personal experience has been that it must be in Drive to regen... ... ... ... .....



Bob

Bob,



My experience with the cab and chassis differs. It appears to continue regeneration in park, at idle as well. I say that with the understanding that I don't truly have a clue what the ECM is doing but can only guess by following my pyro gauge reading.



As I wrote above, if I leave the cruise control button activated at idle the pyro will cool to somewhere around 400* - 600* and remain. If I deactivate the cruise/fast idle button and wait after a minute or two at idle the ECM will ramp up idle speed to 900 rpm and apparently restart regen. Pyro temp then climbs to 600* - 8000* and remains there for several minutes until, apparently regen is satisfied, maybe an abbreviated cook off, then egt drops and idle speed returns to normal.

 

[TKeeler]

Regen's

How difficult could it possibly be to have an indicator light to signal a regen taking place? Maybe even a switch to allow the driver to start one at will. I know all of this has been gone over before but what could possibly prevent them from doing this?I am assuming that some aftermarket programer manufacturers could make something like this for people who want to keep their trucks"green".

When I took my truck in the last time they told me the computer showed I had numerous Regen attempts but hadn't had a successful one in a long time, I am at 20,000 miles. So they cleaned up the o2 sensors and took it out to the freeway for the 45-50 minute drive. My Dashhawk showed 0. 0 for the first time for the 'Regen Filter', the lowest I had ever seen it was 2. 5 which counts down backwards when it goes into 'DeSOx' mode. The 'Desoot' mode seems to happen pretty often and lasts 15-20 minutes. Another of the PID's I can monitor shows the 'Regen Trigger' at 4. 5, I can only assume that when the 'Regen Filter' reaches the 4. 5 figure that it then looks to go into 'DeSOx' or the drive it at highway speed for 45-50 minutes. The 'Desoot' appears to stay active as long as I am in drive even if I am stopped at a light and if I do interrupt it for any reason (in park or shut the truck down) it starts back up the next time I take off. However the 'DeSOx' mode of regen doesn't appear to be so easy. I understand the 45-50 minutes at highway speed but what are the other requirements? It's apparent that once it starts it has to complete the process all at once and wont allow you to stop and continue it the next time you start up. Does anyone know the sequence for this process and it's requirements? What is the minimum speed required or is that even the requirement? What will kill the process and why wont it just start up again like the 'Desoot' does? I don't do much long highway speed driving so when it wants to 'DeSOx' I can pretty much plan on it not being able to complete the process, unless of course they would have provided us with a way to manually force the 'DeSOx' without having a StarScan tool. It's become quiet apparent that the DPF systems on these engines has become a pretty important thing so why not provide some data like we get from our Oil PSI and water temp gauges? We are basically getting 'Idiot light' information via the EVIC when it's too late, kind of like the old low oil pressure light... too little too late.



I really love this truck but would really, really like to know more about what is going on under the hood (or under my seat) than Dodge or Cummins is allowing us to see.

 

[HBarlow]

I really love this truck but would really, really like to know more about what is going on under the hood (or under my seat) than Dodge or Cummins is allowing us to see.

TKeeler,



Me too!

 

[Allnew2Me]

HBarlow, I do remember you asking the questions regarding this issue. I also remember the speaker being familiar with the Dodge trucks or at least telling you that he was. I don't have a new truck but was interested in the info being shared. What I heard and I could be mistaken, was that these trucks are designed to regen without the owner being aware of the process and that shutting down during the process was not a problem at all. It is automated and will resume when the truck reaches the required speed/temp to do so. He did state that if you were pulling hard up a hill and came to a stop it would be wise to allow a certain amount of time to let temps equalize, but other than that shut it down. I don't think that the average owner pays as much attention as we do to the operating details of these trucks. Other than the turbo being cooled, I don't see that the excess heat in the DPF would be any problem since that is what it is for, an oven of sorts. Any engine would benefit from a cooldown period after running hard and certainly letting the pyro tell you when to shut down is not going to cause any harm other than having to wait for it to cool. I can see though that an indicator light would be a nice feature to have.

 

[HBarlow]

When I took my truck in the last time they told me the computer showed I had numerous Regen attempts but hadn't had a successful one in a long time, I am at 20,000 miles. So they cleaned up the o2 sensors and took it out to the freeway for the 45-50 minute drive. My Dashhawk showed 0. 0 for the first time for the 'Regen Filter', the lowest I had ever seen it was 2. 5 which counts down backwards when it goes into 'DeSOx' mode. The 'Desoot' mode seems to happen pretty often and lasts 15-20 minutes. Another of the PID's I can monitor shows the 'Regen Trigger' at 4. 5, I can only assume that when the 'Regen Filter' reaches the 4. 5 figure that it then looks to go into 'DeSOx' or the drive it at highway speed for 45-50 minutes. The 'Desoot' appears to stay active as long as I am in drive even if I am stopped at a light and if I do interrupt it for any reason (in park or shut the truck down) it starts back up the next time I take off. However the 'DeSOx' mode of regen doesn't appear to be so easy. I understand the 45-50 minutes at highway speed but what are the other requirements? It's apparent that once it starts it has to complete the process all at once and wont allow you to stop and continue it the next time you start up. Does anyone know the sequence for this process and it's requirements? What is the minimum speed required or is that even the requirement? What will kill the process and why wont it just start up again like the 'Desoot' does? I don't do much long highway speed driving so when it wants to 'DeSOx' I can pretty much plan on it not being able to complete the process, unless of course they would have provided us with a way to manually force the 'DeSOx' without having a StarScan tool. It's become quiet apparent that the DPF systems on these engines has become a pretty important thing so why not provide some data like we get from our Oil PSI and water temp gauges? We are basically getting 'Idiot light' information via the EVIC when it's too late, kind of like the old low oil pressure light... too little too late.



I really love this truck but would really, really like to know more about what is going on under the hood (or under my seat) than Dodge or Cummins is allowing us to see.

TKeeler:



You referred to "Desoot" and "DeSOx" modes so apparently you have determined that there are two distinctly different regeneration modes. That is completely new information to me. I have never read reports from anyone else who knew this.



It would help explain the behavior of my truck. I have been puzzled by mine going into regeneration mode after driving only a few highway miles early on a morning after spending two or more days on the highway pulling my heavy fiver. I would have thought that steady highway driving under load for 1000 miles should completely clean the dpf.



sag2 appears to be correct that shutting down while in the regen mode won't harm the engine; his statement seems to be backed up by the fact that there are no warnings in the owner's manual. However, there have been several TDR members who have reported CELs and dealer visits for service or repair and they also report, as you did, that when their ECM was scanned it showed numerous failed attempts to complete regeneration. I assume that the dealer techs are blaming the need for a service visit on the failed regen attempts.



I want to learn how to avoid CELs and trips to the dealer for parts replacement and/or service procedures as well as early failure of components after the warranty expires. The 5. 9 ISBs were capable of dependable service life of hundreds of thousands, as much as 1,000,000 miles. , I expect the new 6. 7 engine is capable of the same service life if we learn to use the dpf and cat converter properly.

 

[HBarlow]

HBarlow, I do remember you asking the questions regarding this issue. I also remember the speaker being familiar with the Dodge trucks or at least telling you that he was. I don't have a new truck but was interested in the info being shared. What I heard and I could be mistaken, was that these trucks are designed to regen without the owner being aware of the process and that shutting down during the process was not a problem at all. It is automated and will resume when the truck reaches the required speed/temp to do so. He did state that if you were pulling hard up a hill and came to a stop it would be wise to allow a certain amount of time to let temps equalize, but other than that shut it down. I don't think that the average owner pays as much attention as we do to the operating details of these trucks. Other than the turbo being cooled, I don't see that the excess heat in the DPF would be any problem since that is what it is for, an oven of sorts. Any engine would benefit from a cooldown period after running hard and certainly letting the pyro tell you when to shut down is not going to cause any harm other than having to wait for it to cool. I can see though that an indicator light would be a nice feature to have.

Allnew:



I heard the speaker say the same things but the impression I had was that he doesn't own a 6. 7 Dodge Ram and Cummins Rocky Mountain where he works doesn't sell or service them. My impression was that he was speaking in general terms about his long experience with Cummins engines in general and limited experience with the new 6. 7 engine in a handful of MDTs which use entirely different software and different emissions hardware.



You are correct and I agree that we probably worry too much about proper operation of our engines. Others have told me the same thing but I appreciate good machinery and prefer to care for it properly if possible. Additionally, I simply want to KNOW how the ECM and emissions crap on these new engines work so I can decide for myself how to operate and service it.

 

[Allnew2Me]

HBarlow, That is the great thing about the TDR. Eventually we will find the answer to every question with the help of everyone. I can understand your wanting to know how all the systems work on your truck and it is only a matter of time until the newer systems are understood like the older ones are.

 

[HBarlow]

Allnew,



Yeah, I'm hopeful. If we keep sharing our tiny new bits of knowledge gained with each other and asking questions I am confident that eventually, we will learn how the regeneration mode works and how to use it and avoid related problems.



I occasionally stop to think back to seven years ago when my first ever diesel-powered vehicle, a 2001 Dodge Ram 3500 HO/6 speed, was only a few months old. I didn't know much more than to make sure I put diesel fuel only in the tank at the time.



After seven years of membership in the TDR, several TDR rallies, lots of new friends, reading thousands of posts, and more than a half million essentially trouble free Cummins miles, I know a little about them now. In time I think we'll all understand the complicated new..... what is it? Blu-Tec emissions system?

 

[Soot4Life]

Sorry HBarlow..... According to our Powerstroke friend this site is a stinker so anything you might learn here would be useless. Funny... ... I always thought that the TDR was the hands down finest website of its kind and that I'd learned buckets full of good things here. It goes to show you a person can be wrong. Now where's that 2009 Powerstroke brochure?